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1.
Nutrients ; 16(15)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39125405

RESUMEN

The skin serves as a critical barrier against external threats-dehydration, ultraviolet exposure, and infections-playing a significant role in internal homeostasis and moisture retention. Additionally, and equally importantly, it interacts dynamically with the complex microbiome resident in it, which is essential for maintaining skin health. Recent interest has focused on the use of probiotics and postbiotics, besides their ability to modulate the skin microbiome, to enhance barrier function, and exhibit anti-inflammatory properties, to be involved in skincare, by having the potential to improve skin hydration, elasticity, and overall appearance, as well as in reducing signs of aging, such as wrinkles and fine lines. The products-being a combination of a cosmetic regime plus probiotic[s] or postbiotic[s]-are named cosmeceuticals. However, to comply with the regulations for the characterization of a microorganism as a specific probiotic strain, the pro- or postbiotics incorporated into the cosmetic regime should be both genetically and phenotypically defined. Thus, in this review, we present 14 published clinical trials using such cosmetic products with specific, well-characterized strains of probiotics or postbiotics applied to volunteers with healthy skin. Looking at the results of these studies collectively, we can say that these genetically and phenotypically defined strains of either live or inanimate bacteria and/or their components seem to keep the treated skin at least fully hydrated, with intact epithelial tone, increased radiance, and with decreased wrinkle depth, while normalizing the commensal skin microbiota. Future advancements in personalized skin care may lead to genomic sequencing and metabolomics to tailor probiotic and postbiotic treatments to individual skin microbiomes, promising a new frontier in cosmeceuticals.


Asunto(s)
Cosmecéuticos , Probióticos , Envejecimiento de la Piel , Piel , Probióticos/farmacología , Humanos , Piel/microbiología , Envejecimiento de la Piel/efectos de los fármacos , Microbiota , Ensayos Clínicos como Asunto
2.
Haematologica ; 2024 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-38841782

RESUMEN

Non-Hodgkin lymphomas (NHL) commonly occur in immune-deficient (ID) patients, both HIV-infected and transplanted, and are often EBV-driven with cerebral localization, raising the question of tumor immunogenicity, a critical issue for treatment responses. We investigated the immunogenomics of 68 lymphoproliferative disorders from 51 ID (34 posttransplant, 17 HIV+) and 17 immunocompetent patients. Overall, 72% were Large B Cells Lymphoma (LBCL) and 25% were primary central-nervous-system lymphoma (PCNSL) while 40% were EBV-positive. Tumor whole-exome and RNA sequencing, along with a bioinformatics pipeline allowed analysis of tumor mutational burden (TMB), tumor landscape and microenvironment (TME) and prediction of tumor neoepitopes. Both TMB (2.2 vs 3.4/Mb, p=0.001) and neoepitopes numbers (40 vs 200, p=0.00019) were lower in EBVpositive than in EBV-negative NHL, regardless of the immune status. In contrast both EBV and the immune status influenced the tumor mutational profile, with HNRNPF and STAT3 mutations exclusively observed in EBV-positive and ID NHL, respectively. Peripheral blood T-cell responses against tumor neoepitopes were detected in all EBV-negative cases but in only half EBV-positive ones, including responses against IgH-derived MHC-class-II restricted neoepitopes. The TME analysis showed higher CD8 T cell infiltrates in EBVpositive vs EBV-negative NHL, together with a more tolerogenic profile composed of Tregs, type-M2 macrophages and an increased expression of negative immune-regulators. Our results highlight that the immunogenomics of NHL in patients with immunodeficiency primarily relies on the tumor EBV status, while T cell recognition of tumor- and IgH-specific neoepitopes is conserved in EBV-negative patients, offering potential opportunities for future T cell-based immune therapies.

3.
J Immunol Methods ; 531: 113712, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38906414

RESUMEN

During SARS-CoV-2 pandemic, the assessment of immune protection of people at risk of severe infection was an important goal. The appearance of VOCs (Variant of Concern) highlighted the limits of evaluating immune protection through the humoral response. While the humoral response partly loses its neutralizing activity, the anti-SARS-CoV-2 memory T cell response strongly cross protects against VOCs becoming an indispensable tool to assess immune protection. We compared two techniques available in laboratory to evaluate anti-SARS-CoV-2 memory T cell response in a cohort of infected or vaccinated patients with different levels of risk to develop a severe disease: the ELISpot assay and the T-Cell Lymphocyte Proliferation Assay respectively exploring IFNγ production and cell proliferation. We showed that the ELISpot assay detected more anti-Spike memory T cell response than the Lymphocyte Proliferation Assay. We next observed that the use of two different suppliers as antigenic source in the ELISpot assay did not affect the detection of anti-Spike memory T cell response. Finally, we explored a new approach for defining the positivity threshold, using unsupervised mixed Gaussian modeling, challenging the traditional ROC curve used by the supplier. That will be helpful in endemic situation where it could be difficult to recruit "negative" patients.


Asunto(s)
COVID-19 , Ensayo de Immunospot Ligado a Enzimas , Células T de Memoria , SARS-CoV-2 , Humanos , COVID-19/inmunología , COVID-19/epidemiología , SARS-CoV-2/inmunología , Células T de Memoria/inmunología , Masculino , Femenino , Persona de Mediana Edad , Proliferación Celular , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Adulto , Anciano , Interferón gamma/inmunología , Interferón gamma/metabolismo , Glicoproteína de la Espiga del Coronavirus/inmunología , Memoria Inmunológica
4.
J Clin Med ; 12(24)2023 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-38137802

RESUMEN

Two semi-quantitative, Luminex-based, single-antigen bead (SAB) assays are available to detect anti-HLA antibodies and evaluate their reactivity with complement binding. Sera from 97 patients with positive panel reactive antibody tests (>5%) were analyzed with two SAB tests, Immucor (IC) and One-Lambda (OL), for anti-HLA antibody detection and the evaluation of their complement-binding capacity. IC detected 1608/8148 (mean fluorescent intensity (MFI) 4195 (1995-11,272)) and 1136/7275 (MFI 6706 (2647-13,184)) positive anti-HLA class I and II specificities, respectively. Accordingly, OL detected 1942/8148 (MFI 6185 (2855-12,099)) and 1247/7275 (MFI 9498 (3630-17,702)) positive anti-HLA class I and II specificities, respectively. For the IC assay, 428/1608 (MFI 13,900 (9540-17,999)) and 409/1136 (MFI 11,832 (7128-16,531)) positive class I and II specificities bound C3d, respectively. Similarly, OL detected 485/1942 (MFI 15,452 (9369-23,095)) and 298/1247 (MFI18,852 (14,415-24,707)) C1q-binding class I and II specificities. OL was more sensitive in detecting class I and II anti-HLA antibodies than IC was, although there was no significant difference in the number of class II specificities per case. MFI was higher for complement vs. non-complement-binding anti-HLA antibodies in both assays. Both methods were equal in detecting complement-binding anti-HLA class I antibodies, whereas the C3d assay was more sensitive in detecting complement-binding anti-HLA class II antibodies.

5.
Development ; 150(21)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37882832

RESUMEN

In most organisms, 3D growth takes place at the onset of embryogenesis. In some brown algae, 3D growth occurs later in development, when the organism consists of several hundred cells. We studied the cellular events that take place when 3D growth is established in the embryo of the brown alga Saccharina, a kelp species. Semi-thin sections, taken from where growth shifts from 2D to 3D, show that 3D growth first initiates from symmetrical cell division in the monolayered lamina, and then is enhanced through a series of asymmetrical cell divisions in a peripheral monolayer of cells called the meristoderm. Then, daughter cells rapidly differentiate into cortical and medullary cells, characterised by their position, size and shape. In essence, 3D growth in kelps is based on a series of differentiation steps that occur rapidly after the initiation of a bilayered lamina, followed by further growth of the established differentiated tissues. Our study depicts the cellular landscape necessary to study cell-fate programming in the context of a novel mode of 3D growth in an organism phylogenetically distant from plants and animals.


Asunto(s)
Escarabajos , Kelp , Phaeophyceae , Animales , División Celular , Diferenciación Celular , Desarrollo Embrionario
6.
Cancers (Basel) ; 15(14)2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37509354

RESUMEN

There is an imminent need for novel strategies for the diagnosis and treatment of aggressive triple-negative breast cancer (TNBC). Cell-targeted multifunctional nanomaterials hold great potential, as they can combine precise early-stage diagnosis with local therapeutic delivery to specific cell types. In this study, we used mesoporous silica (MS)-coated gold nanobipyramids (MS-AuNBPs) for fluorescence imaging in the near-infrared (NIR) biological window, along with targeted TNBC treatment. Our MS-AuNBPs, acting partly as light amplification components, allow considerable metal-enhanced fluorescence for a NIR dye conjugated to their surfaces compared to the free dye. Fluorescence analysis confirms a significant increase in the dye's modified quantum yield, indicating that MS-AuNBPs can considerably increase the brightness of low-quantum-yield NIR dyes. Meanwhile, we tested the chemotherapeutic efficacy of MS-AuNBPs in TNBC following the loading of doxorubicin within the MS pores and functionalization to target folate receptor alpha (FRα)-positive cells. We show that functionalized particles target FRα-positive cells with significant specificity and have a higher potency than free doxorubicin. Finally, we demonstrate that FRα-targeted particles induce stronger antitumor effects and prolong overall survival compared to the clinically applied non-targeted nanotherapy, Doxil. Together with their excellent biocompatibility measured in vitro, this study shows that MS-AuNBPs are promising tools to detect and treat TNBCs.

7.
J Clin Med ; 11(23)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36498621

RESUMEN

Current pre-transplantation routine matching involves serum anti-HLA antibodies quantification but cannot always preclude unfavorable graft outcomes. Epitope-based matching is proposed as a more precise approach, but to date no epitope-matching algorithm provides a satisfactory predictive tool for transplantation outcomes. In this study, anti-HLA-II loci responses from 1748 patients were analyzed with unsupervised machine learning algorithms, namely principal component analysis (PCA) and antigenic distances, projected as dendrograms. PCA for anti-HLA-DR anti-bodies revealed three main clusters of responses: anti-HLA-DR51 combined with anti-HLA-DRB1*01, anti-HLA-DR52 combined with anti-HLA-DRB1*08 and anti-HLA-DR53 combined with anti-HLA-DRB1*10. The dendrogram for anti-HLA-DR confirmed the pattern and showed further bisection of each cluster. Common epitopes present exclusively in all HLA molecules of each cluster were determined following the HLA epitope registry. Thus, we propose that 19 out of 123 HLA-DR epitopes are those that mainly lead anti-HLA-DR responses in the studied population. Likewise, we identified 22 out of 83 epitopes responsible for anti-HLA-DQ and 13 out of 62 responsible for anti-HLA-DP responses. Interpretation of these results may elucidate mechanisms of interlocus cross-reactivity, providing an alternative way of estimating the significance of each epitope in a population and thus suggesting a novel strategy towards optimal donor selection.

9.
Front Immunol ; 13: 841031, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35615367

RESUMEN

End stage renal disease (ESRD) engenders detrimental effects in the Immune system, manifested as quantitative alterations of lymphocyte subpopulations, akin, albeit not identical to those observed during the ageing process. We performed dimensionality reduction of an extended lymphocyte phenotype panel of senescent and exhaustion related markers in ESRD patients and controls with Principal Component Analysis (PCA) and Uniform Manifold Approximation and Projection (UMAP). The plane defined by the first two principal components of PCA showed two fuzzy clusters, for patients and controls, respectively, with loadings of non-senescent markers pointing towards the controls' centroid. Naive lymphocytes were reduced in ESRD patients compared to controls (CD4+CD45RA+CCR7+ 200(150-328) vs. 426(260-585cells/µl respectively, P = 0.001, CD19+IgD+CD27- 54(26-85) vs. 130(83-262)cells/µl respectively, P < 0.001). PCA projections of the multidimensional ESRD immune phenotype suggested a more senescent phenotype in hemodialysis compared to hemodiafiltration treated patients. Lastly, clustering based on UMAP revealed three distinct patient groups, exhibiting gradual changes for naive, senescent, and exhausted lymphocyte markers. Machine learning algorithms can distinguish ESRD patients from controls, based on their immune-phenotypes and also, unveil distinct immunological groups within patients' cohort, determined possibly by dialysis prescription.


Asunto(s)
Fallo Renal Crónico , Algoritmos , Análisis por Conglomerados , Humanos , Fallo Renal Crónico/terapia , Linfocitos , Diálisis Renal
11.
J Vis Exp ; (181)2022 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-35343968

RESUMEN

In Saccharina latissima, the embryo develops as a monolayered cell sheet called the lamina or the blade. Each embryo cell is easy to observe, readily distinguishable from its neighbors, and can be individually targeted. For decades, laser ablation has been used to study embryo development. Here, a protocol for cell-specific laser ablation was developed for early embryos of the brown alga S. latissima. The presented work includes: (1) the preparation of Saccharina embryos, with a description of the critical parameters, including culture conditions, (2) the laser ablation settings, and (3) the monitoring of the subsequent growth of the irradiated embryo using time-lapse microscopy. In addition, details are provided on the optimal conditions for transporting the embryos from the imaging platform back to the lab, which can profoundly affect subsequent embryo development. Algae belonging to the order Laminariales display embryogenesis patterns similar to Saccharina; this protocol can thus be easily transferred to other species in this taxon.


Asunto(s)
Terapia por Láser , Phaeophyceae , Embrión de Mamíferos , Desarrollo Embrionario
12.
Front Immunol ; 12: 670956, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34386000

RESUMEN

Detection of alloreactive anti-HLA antibodies is a frequent and mandatory test before and after organ transplantation to determine the antigenic targets of the antibodies. Nowadays, this test involves the measurement of fluorescent signals generated through antibody-antigen reactions on multi-beads flow cytometers. In this study, in a cohort of 1,066 patients from one country, anti-HLA class I responses were analyzed on a panel of 98 different antigens. Knowing that the immune system responds typically to "shared" antigenic targets, we studied the clustering patterns of antibody responses against HLA class I antigens without any a priori hypothesis, applying two unsupervised machine learning approaches. At first, the principal component analysis (PCA) projections of intra-locus specific responses showed that anti-HLA-A and anti-HLA-C were the most distantly projected responses in the population with the anti-HLA-B responses to be projected between them. When PCA was applied on the responses against antigens belonging to a single locus, some already known groupings were confirmed while several new cross-reactive patterns of alloreactivity were detected. Anti-HLA-A responses projected through PCA suggested that three cross-reactive groups accounted for about 70% of the variance observed in the population, while anti-HLA-B responses were mainly characterized by a distinction between previously described Bw4 and Bw6 cross-reactive groups followed by several yet undocumented or poorly described ones. Furthermore, anti-HLA-C responses could be explained by two major cross-reactive groups completely overlapping with previously described C1 and C2 allelic groups. A second feature-based analysis of all antigenic specificities, projected as a dendrogram, generated a robust measure of allelic antigenic distances depicting bead-array defined cross reactive groups. Finally, amino acid combinations explaining major population specific cross-reactive groups were described. The interpretation of the results was based on the current knowledge of the antigenic targets of the antibodies as they have been characterized either experimentally or computationally and appear at the HLA epitope registry.


Asunto(s)
Biología Computacional/métodos , Antígenos HLA-A/inmunología , Antígenos HLA-B/inmunología , Antígenos HLA-C/inmunología , Trasplante de Órganos , Adulto , Anciano , Estudios de Cohortes , Reacciones Cruzadas , Epítopos , Humanos , Isoanticuerpos/sangre , Aprendizaje Automático , Persona de Mediana Edad , Análisis de Componente Principal , Sistema de Registros , Inmunología del Trasplante
13.
Haematologica ; 106(8): 2233-2241, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32675224

RESUMEN

Human immunodeficiency virus (HIV) infection is associated with an increased risk of non-Hodgkin lymphoma (NHL). Even in the era of suppressive antiretroviral treatment, HIV-infected individuals remain at higher risk of developing NHL compared to the general population. To identify potential genetic risk loci, we performed case-control genome-wide association studies and a meta-analysis across three cohorts of HIV+ patients of European ancestry, including a total of 278 cases and 1924 matched controls. We observed a significant association with NHL susceptibility in the C-X-C motif chemokine ligand 12 (CXCL12) region on chromosome 10. A fine mapping analysis identified rs7919208 as the most likely causal variant (P = 4.77e-11), with the G>A polymorphism creating a new transcription factor binding site for BATF and JUND. These results suggest a modulatory role of CXCL12 regulation in the increased susceptibility to NHL observed in the HIV-infected population.


Asunto(s)
Infecciones por VIH , Linfoma Relacionado con SIDA , Linfoma no Hodgkin , Antirretrovirales/uso terapéutico , Estudios de Casos y Controles , Quimiocina CXCL12 , Estudio de Asociación del Genoma Completo , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Humanos , Linfoma Relacionado con SIDA/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/genética , Polimorfismo Genético
14.
Front Immunol ; 11: 1667, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32849576

RESUMEN

Allele specific antibody response against the polymorphic system of HLA is the allogeneic response marker determining the immunological risk for graft acceptance before and after organ transplantation and therefore routinely studied during the patient's workup. Experimentally, bead bound antigen- antibody reactions are detected using a special multicolor flow cytometer (Luminex). Routinely for each sample, antibody responses against 96 different HLA antigen groups are measured simultaneously and a 96-dimensional immune response vector is created. Under a common experimental protocol, using unsupervised clustering algorithms, we analyzed these immune intensity vectors of anti HLA class II responses from a dataset of 1,748 patients before or after renal transplantation residing in a single country. Each patient contributes only one serum sample in the analysis. A population view of linear correlations of hierarchically ordered fluorescence intensities reveals patterns in human immune responses with striking similarities with the previously described CREGs but also brings new information on the antigenic properties of class II HLA molecules. The same analysis affirms that "public" anti-DP antigenic responses are not correlated to anti DR and anti DQ responses which tend to cluster together. Principal Component Analysis (PCA) projections also demonstrate ordering patterns clearly differentiating anti DP responses from anti DR and DQ on several orthogonal planes. We conclude that a computer vision of human alloresponse by use of several dimensionality reduction algorithms rediscovers proven patterns of immune reactivity without any a priori assumption and might prove helpful for a more accurate definition of public immunogenic antigenic structures of HLA molecules. Furthermore, the use of Eigen decomposition on the Immune Response generates new hypotheses that may guide the design of more effective patient monitoring tests.


Asunto(s)
Citometría de Flujo , Antígenos HLA/inmunología , Prueba de Histocompatibilidad , Histocompatibilidad , Isoanticuerpos/sangre , Isoantígenos/inmunología , Trasplante de Riñón , Aprendizaje Automático , Reconocimiento de Normas Patrones Automatizadas , Adulto , Análisis por Conglomerados , Femenino , Rechazo de Injerto/sangre , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Inmunosupresores/uso terapéutico , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Resultado del Tratamiento
15.
Commun Biol ; 3(1): 177, 2020 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-32313116

RESUMEN

Buruli ulcer, caused by Mycobacterium ulcerans and characterized by devastating necrotizing skin lesions, is the third mycobacterial disease worldwide. The role of host genetics in susceptibility to Buruli ulcer has long been suggested. We conduct the first genome-wide association study of Buruli ulcer on a sample of 1524 well characterized patients and controls from rural Benin. Two-stage analyses identify two variants located within LncRNA genes: rs9814705 in ENSG00000240095.1 (P = 2.85 × 10-7; odds ratio = 1.80 [1.43-2.27]), and rs76647377 in LINC01622 (P = 9.85 × 10-8; hazard ratio = 0.41 [0.28-0.60]). Furthermore, we replicate the protective effect of allele G of a missense variant located in ATG16L1, previously shown to decrease bacterial autophagy (rs2241880, P = 0.003; odds ratio = 0.31 [0.14-0.68]). Our results suggest LncRNAs and the autophagy pathway as critical factors in the development of Buruli ulcer.


Asunto(s)
Proteínas Relacionadas con la Autofagia/genética , Autofagia/genética , Úlcera de Buruli/genética , Mutación Missense , Mycobacterium ulcerans/patogenicidad , Polimorfismo de Nucleótido Simple , ARN Largo no Codificante/genética , Adolescente , Adulto , Benin , Úlcera de Buruli/diagnóstico , Úlcera de Buruli/microbiología , Estudios de Casos y Controles , Niño , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Interacciones Huésped-Patógeno , Humanos , Masculino , Fenotipo , Medición de Riesgo , Factores de Riesgo , Adulto Joven
16.
Nanoscale Adv ; 2(12): 5635-5647, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34381958

RESUMEN

Background: The toxicity of inhaled silver nanoparticles on contractile and pro-inflammatory airway smooth muscle cells (ASMCs) that control airway calibre is unknown. We explored the oxidative activities and sulfidation processes of the toxic-inflammatory response. Method: Silver nanospheres (AgNSs) of 20 nm and 50 nm diameter and silver nanowires (AgNWs), short S-AgNWs, 1.5 µm and long L-AgNWs, 10 µm, both 72 nm in diameter were manufactured. We measured their effects on cell proliferation, mitochondrial reactive oxygen species (ROS) release and membrane potential, and also performed electron microscopic studies. Main results and findings: The greatest effects were observed for the smallest particles with the highest specific surface area and greatest solubility that were avidly internalised. ASMCs exposed to 20 nm AgNSs (25 µg mL-1) for 72 hours exhibited a significant decrease in DNA incorporation (-72.4%; p < 0.05), whereas neither the 50 nm AgNSs nor the s-AgNWs altered DNA synthesis or viability. There was a small reduction in ASMC proliferation for the smaller AgNS, although Ag+ at 25 µL mL-1 reduced DNA synthesis by 93.3% (p < 0.001). Mitochondrial potential was reduced by both Ag+ (25 µg mL-1) by 47.1% and 20 nm Ag NSs (25 µg mL-1) by 40.1% (*both at p < 0.05), but was not affected by 50 nm AgNSs and the AgNWs. None of the samples showed a change in ROS toxicity. However, malondialdehyde release, associated with greater total ROS, was observed for all AgNPs, to an extent following the geometric size (20 nm AgNS: 213%, p < 0.01; 50 nm AgNS: 179.5%, p < 0.01 and L-AgNWs by 156.2%, p < 0.05). The antioxidant, N-acetylcysteine, prevented the reduction in mitochondrial potential caused by 20 nm AgNSs. The smaller nanostructures were internalised and dissolved within the ASMCs with the formation of non-reactive silver sulphide (Ag2S) on their surface, but with very little uptake of L-AgNWs. When ASMCs were incubated with H2S-producing enzyme inhibitors, the spatial extent of Ag2S formation was much greater. Conclusion: The intracellular toxicity of AgNPs in ASMCs is determined by the solubility of Ag+ released and the sulfidation process, effects related to particle size and geometry. Passivation through sulfidation driven by biogenic H2S can outcompete dissolution, thus reducing the toxicity of the smaller intracellular Ag nanostructures.

17.
Front Genet ; 10: 1024, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31749832

RESUMEN

Despite the astonishing progress in treating chronic hepatitis C virus (HCV) infection with direct-acting antiviral agents, liver fibrosis remains a major health concern in HCV infected patients, in particular due to the treatment cost and insufficient HCV screening in many countries. Only a fraction of patients with chronic HCV infection develop liver fibrosis. While there is evidence that host genetic factors are involved in the development of liver fibrosis, the common variants identified so far, in particular by genome-wide association studies, were found to have limited effects. Here, we conducted an exome association study in 88 highly selected HCV-infected patients with and without fibrosis. A strategy focusing on TGF-ß pathway genes revealed an enrichment in rare variants of the endoglin gene (ENG) in fibrosis patients. Replication studies in additional cohorts (617 patients) identified one specific ENG variant, Thr5Met, with an overall odds ratio for fibrosis development in carriers of 3.04 (1.39-6.69). Our results suggest that endoglin, a key player in TGF-ß signaling, is involved in HCV-related liver fibrogenesis.

18.
Anal Chem ; 91(17): 11098-11107, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31310103

RESUMEN

There are no methods sensitive enough to detect enzymes within cells, without the use of analyte labeling. Here we show that it is possible to detect protein ion signals of three different H2S-synthesizing enzymes inside microglia after pretreatment with silver nanowires (AgNW) using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Protein fragment ions, including the fragment of amino acid (C4H8N+ = 70 amu), fragments of the sulfur-producing cystathionine-containing enzymes, and the Ag+ ion signal could be detected without the use of any labels; the cells were mapped using the C4H8N+ amino acid fragment. Scanning electron microscopy imaging and energy-dispersive X-ray chemical analysis showed that the AgNWs were inside the same cells imaged by TOF-SIMS and transformed chemically into crystalline Ag2S within cells in which the sulfur-producing proteins were detected. The presence of these sulfur-producing cystathionine-containing enzymes within the cells was confirmed by Western blots and confocal microscopy images of fluorescently labeled antibodies against the sulfur-producing enzymes. Label-free TOF-SIMS is very promising for the label-free identification of H2S-contributing enzymes and their cellular localization in biological systems. The technique could in the future be used to identify which of these enzymes are most contributory.


Asunto(s)
Cistationina betasintasa/metabolismo , Cistationina gamma-Liasa/metabolismo , Microglía/enzimología , Plata/farmacología , Azufre/química , Sulfurtransferasas/metabolismo , Animales , Transporte Biológico , Línea Celular Transformada , Ratones , Microglía/efectos de los fármacos , Microglía/ultraestructura , Microscopía Electrónica de Rastreo , Imagen Molecular/instrumentación , Imagen Molecular/métodos , Nanocables/química , Plata/química , Espectrometría de Masa de Ion Secundario , Azufre/metabolismo
19.
ACS Appl Mater Interfaces ; 11(26): 23083-23092, 2019 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-31252484

RESUMEN

Metal-enhanced fluorescence (MEF), resulting from the near-field interaction of fluorophores with metallic nanostructures, has emerged as a powerful tool for dramatically improving the performance of fluorescence-based biomedical applications. Allowing for lower autofluorescence and minimal photoinduced damage, the development of multifunctional and multiplexed MEF platforms in the near-infrared (NIR) windows is particularly desirable. Here, a low-cost fabrication method based on nanosphere lithography is applied to produce tunable three-dimensional (3D) gold (Au) nanohole-disc arrays (Au-NHDAs). The arrays consist of nanoscale glass pillars atop nanoholes in a Au thin film: the top surfaces of the pillars are Au-covered (effectively nanodiscs), and small Au nanoparticles (nanodots) are located on the sidewalls of the pillars. This 3D hole-disc (and possibly nanodot) construct is critical to the properties of the device. The versatility of our approach is illustrated through the production of uniform and highly reproducible Au-NHDAs with controlled structural properties and tunable optical features in the NIR windows. Au-NHDAs allow for a very large NIR fluorescence enhancement (more than 400 times), which is attributed to the 3D plasmonic structure of the arrays that allows strong surface plasmon polariton and localized surface plasmon resonance coupling through glass nanogaps. By considering arrays with the same resonance peak and the same nanodisc separation distance, we show that the enhancement factor varies with nanodisc diameter. Using computational electromagnetic modeling, the electric field enhancement at 790 nm was calculated to provide insights into excitation enhancement, which occurs due to an increase in the intensity of the electric field. Fluorescence lifetime measurements indicate that the total fluorescence enhancement may depend on controlling excitation enhancement and therefore the array morphology. Our findings provide important insights into the mechanism of MEF from 3D plasmonic arrays and establish a low-cost versatile approach that could pave the way for novel NIR-MEF bioapplications.


Asunto(s)
Investigación Biomédica , Nanopartículas del Metal/química , Nanoestructuras/química , Fluorescencia , Colorantes Fluorescentes/química , Colorantes Fluorescentes/provisión & distribución , Oro/química , Nanopartículas del Metal/uso terapéutico , Nanosferas/química , Resonancia por Plasmón de Superficie
20.
Nanoscale ; 11(27): 12858-12870, 2019 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-31157349

RESUMEN

There is a need for novel strategies to treat aggressive breast cancer subtypes and overcome drug resistance. ZnO nanoparticles (NPs) have potential in cancer therapy due to their ability to potently and selectively induce cancer cell apoptosis. Here, we tested the in vitro chemotherapeutic efficacy of ZnONPs loaded via a mesoporous silica nanolayer (MSN) towards drug-sensitive breast cancer cells (MCF-7: estrogen receptor-positive, CAL51: triple-negative) and their drug-resistant counterparts (MCF-7TX, CALDOX). ZnO-MSNs were coated on to gold nanostars (AuNSs) for future imaging capabilities in the NIR-II range. Electron and confocal microscopy showed that MSN-ZnO-AuNSs accumulated close to the plasma membrane and were internalized by cells. High-resolution electron microscopy showed that MSN coating degraded outside the cells, releasing ZnONPs that interacted with cell membranes. MSN-ZnO-AuNSs efficiently reduced the viability of all cell lines, and CAL51/CALDOX cells were more susceptible than MCF7/MCF-7-TX cells. MSN-ZnO-AuNSs were then conjugated with the antibody to Frizzled-7 (FZD-7), the receptor upregulated by several breast cancer cells. We used the disulphide (S-S) linker that could be cleaved with a high concentration of glutathione normally observed within cancer cells, releasing Zn2+ into the cytoplasm. FZD-7 targeting resulted in approximately three-fold amplified toxicity of MSN-ZnO-AuNSs towards the MCF-7TX drug-resistant cell line with the highest FZD-7 expression. This study shows that ZnO-MSs are promising tools to treat triple-negative and drug-resistant breast cancers and highlights the potential clinical utility of FZD-7 for delivery of nanomedicines and imaging probes specifically to these cancer types.


Asunto(s)
Antineoplásicos Inmunológicos , Neoplasias de la Mama/tratamiento farmacológico , Portadores de Fármacos , Receptores Frizzled/antagonistas & inhibidores , Nanopartículas , Óxido de Zinc , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos Inmunológicos/química , Antineoplásicos Inmunológicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Supervivencia Celular , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Liberación de Fármacos , Femenino , Receptores Frizzled/metabolismo , Humanos , Células MCF-7 , Nanopartículas/química , Nanopartículas/uso terapéutico , Óxido de Zinc/química , Óxido de Zinc/farmacología
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